1. Field of the Invention
The present invention relates to methods of producing monomeric acrylate esters. More specifically it relates to methods of producing acrylate esters by reacting an .alpha.,.beta.-unsaturated acrylic organic acid halide and a hydroxyl containing organic compound in the presence of molecular sieves. In some instances novel acrylate ester monomers are produced.
2. Prior Art
Liquid processes for the syntheses of monomeric acrylate esters have normally required many steps and have produced the desired reaction products in only limited yields. In one prior art reaction system when methacryloyl chloride and an alcohol have been reacted in the presence of triethylamine, monomeric methacrylate esters are produced in only about 30% to about 45% isolated yield. In another prior art reaction system, transesterification of methyl methacrylate with alcohol and an acid catalyst, has also resulted in a low monomeric ester yield. In these typical prior art reactions it is believed that traces of free hydrogen halide acid in the reaction system has favored the competing polymerization reaction of the reactive .alpha.,.beta.-unsaturated esters. This has resulted in the production of unwanted polymers which causes low yield of the desired ester monomer. Either the unreacted starting materials or other products produced during such prior art reactions often exhibit boiling points closely approximating those of the desired monomer, and are thus difficult to separate from the ester monomer by distillation. Furthermore, once acrylate monomers are produced by prior art techniques they remain susceptible to polymerization, and thus further reduce the isolable yield of ester during both purification and storage.
Molecular sieves have been utilized as drying agents for organic solvents, to trap water generated during reactions and to scavenge small molecules. They have not been known to be previously utilized in the production of monomeric acrylate esters.